Clinical characteristics and sick leave associated with infectious mononucleosis in a real-world setting in Germany

BACKGROUND

Infectious mononucleosis (IM), mainly caused by the Epstein-Barr virus, can result in prolonged symptoms. The objective of this study was to look at the length of sick leave, diagnosis of IM, treatment and comorbidities in a real-world setting in Germany.

METHODS

This retrospective, cross-sectional study used electronic medical record data from office-based practices in Germany and included patients with an initial confirmed diagnosis of IM between the 1 January 1 2016 and December 31 2018. Patients of working age (18-65 years) with statutory health insurance were included in order to look at the working population who would need a sick note for their employers in case of illness.

RESULTS

Epstein-Barr virus was the most common cause of IM in this population of 1,596 patients with an average age of 32 years. The majority of patients were women in all cohorts (~60%). Although CFS, myocarditis and thrombocytopenia were not recorded frequently around the index date, the occurrence did increase during the follow-up period. Around half of patients received antibiotics. About 62% of all patients were on sick leave for an average of 20 calendar days around the time of their IM diagnosis. Only 1% were still on sick leave after 6 months.

CONCLUSIONS

A small percentage of patients remained on continuous sick leave after 6 months, suggesting that the long-term effect of IM on the ability to work was minor in our cohort. However, patients could still be experiencing symptoms that influence their quality of life.

Pathway analysis of genetic variants in folate-mediated one-carbon metabolism-related genes and survival in a prospectively followed cohort of colorectal cancer patients

Folate-mediated one-carbon metabolism (FOCM) is a key pathway essential for nucleotide synthesis, DNA methylation, and repair. This pathway is a critical target for 5-fluorouracil (5-FU), which is predominantly used for colorectal cancer (CRC) treatment. A comprehensive assessment of polymorphisms in FOCM-related genes and their association with prognosis has not yet been performed. Within 1,739 CRC cases aged ≥30 years diagnosed from 2003 to 2007 (DACHS study), we investigated 397 single nucleotide polymorphisms (SNPs) and 50 candidates in 48 FOCM-related genes for associations with overall- (OS) and disease-free survival (DFS) using multiple Cox regression (adjusted for age, sex, stage, grade, BMI, and alcohol). We investigated effect modification by 5-FU-based chemotherapy and assessed pathway-specific effects. Correction for multiple testing was performed using false discovery rates (FDR). After a median follow-up time of 5.0 years, 585 patients were deceased. For one candidate SNP in MTHFR and two in TYMS, we observed significant inverse associations with OS (MTHFR: rs1801133, C677T: HRhet  = 0.81, 95% CI: 0.67-0.97; TYMS: rs1001761: HRhet  = 0.82, 95% CI: 0.68-0.99 and rs2847149: HRhet  = 0.82, 95% CI: 0.68-0.99). After FDR correction, one polymorphism in paraoxonase 1 (PON1; rs3917538) was significantly associated with OS (HRhet  = 1.28, 95% CI: 1.07-1.53; HRhzv  = 2.02, 95% CI:1.46-2.80; HRlogAdd  = 1.31, pFDR  = 0.01). Adjusted pathway analyses showed significant associations for pyrimidine biosynthesis (P = 0.04) and fluorouracil drug metabolism (P < 0.01) with significant gene-chemotherapy interactions, including PON1 rs3917538. This study supports the concept that FOCM-related genes could be associated with CRC survival and may modify effects of 5-FU-based chemotherapy in genes in pyrimidine and fluorouracil metabolism, which are relevant targets for therapeutic response and prognosis in CRC. These results require confirmation in additional clinical studies.

Nucleotide excision repair and response and survival to chemotherapy in colorectal cancer patients

Several new chemotherapeutic agents have become available for the treatment of colorectal cancer, which has led to increased complexity in treatment planning. Treatment decision making for individual patients could be facilitated if guided by predictive and prognostic markers. As most cytotoxic drugs induce DNA damage, the DNA damage repair pathways hold potential for yielding such biomarkers. Here, we review the current evidence of a possible involvement of the nucleotide excision repair pathway in the efficacy of chemotherapeutic agents used in the treatment of colorectal cancer. Although a large number of studies have been conducted, they are generally of moderate size and heterogeneous in design. Up to date no firm conclusions can be drawn to translate these results into the clinic. We recommend further comprehensive investigations of the nucleotide excision repair pathway in large patient studies that include both discovery and validation cohorts.

SNPs in transporter and metabolizing genes as predictive markers for oxaliplatin treatment in colorectal cancer patients

Oxaliplatin is frequently used as part of a chemotherapeutic regimen with 5-fluorouracil in the treatment of colorectal cancer (CRC). The cellular availability of oxaliplatin is dependent on metabolic and transporter enzymes. Variants in genes encoding these enzymes may cause variation in response to oxaliplatin and could be potential predictive markers. Therefore, we used a two-step procedure to comprehensively investigate 1,444 single nucleotide polymorphisms (SNPs) from these pathways for their potential as predictive markers for oxaliplatin treatment, using 623 stage II-IV CRC patients (of whom 201 patients received oxaliplatin) from a German prospective patient cohort treated with adjuvant or palliative chemotherapy. First, all genes were screened using the global test that evaluated SNP*oxaliplatin interaction terms per gene. Second, one model was created by backward elimination on all SNP*oxaliplatin interactions of the selected genes. The statistical procedure was evaluated using bootstrap analyses. Nine genes differentially associated with overall survival according to oxaliplatin treatment (unadjusted p values < 0.05) were selected. Model selection resulted in the inclusion of 14 SNPs from eight genes (six transporter genes, ABCA9, ABCB11, ABCC10, ATP1A1, ATP1B2, ATP8B3, and two metabolism genes GSTM5, GRHPR), which significantly improved model fit. Using bootstrap analysis we show an improvement of the prediction error of 3.7% in patients treated with oxaliplatin. Several variants in genes involved in metabolism and transport could thus be potential predictive markers for oxaliplatin treatment in CRC patients. If confirmed, inclusion of these variants in a predictive test could identify patients who are more likely to benefit from treatment with oxaliplatin.

Common genetic variation and survival after colorectal cancer diagnosis: a genome-wide analysis

Genome-wide association studies have identified several germline single nucleotide polymorphisms (SNPs) significantly associated with colorectal cancer (CRC) incidence. Common germline genetic variation may also be related to CRC survival. We used a discovery-based approach to identify SNPs related to survival outcomes after CRC diagnosis. Genome-wide genotyping arrays were conducted for 3494 individuals with invasive CRC enrolled in six prospective cohort studies (median study-specific follow-up = 4.2-8.1 years). In pooled analyses, we used Cox regression to assess SNP-specific associations with CRC-specific and overall survival, with additional analyses stratified by stage at diagnosis. Top findings were followed-up in independent studies. A P value threshold of P < 5×10(-8) in analyses combining discovery and follow-up studies was required for genome-wide significance. Among individuals with distant-metastatic CRC, several SNPs at 6p12.1, nearest the ELOVL5 gene, were statistically significantly associated with poorer survival, with the strongest associations noted for rs209489 [hazard ratio (HR) = 1.8, P = 7.6×10(-10) and HR = 1.8, P = 3.7×10(-9) for CRC-specific and overall survival, respectively). No SNPs were statistically significantly associated with survival among all cases combined or in cases without distant-metastases. SNPs in 6p12.1/ELOVL5 were associated with survival outcomes in individuals with distant-metastatic CRC, and merit further follow-up for functional significance. Findings from this genome-wide association study highlight the potential importance of genetic variation in CRC prognosis and provide clues to genomic regions of potential interest.

Abstract 4590: Polymorphisms in cell-cycle related genes modify the effect of NSAIDs on the risk of colorectal cancer

The risk of colorectal cancer (CRC) is determined by the interplay of genetic and environmental factors. The aim of this study was to identify the association between polymorphisms in cell-cycle related genes and risk of colorectal cancer, and to evaluate the interaction with non-steroidal anti-inflammatory drug (NSAID) use.

Patients with incident CRC were recruited in the framework of DACHS, a German population based case-control study. Altogether, 1756 cases and 1781 controls were genotyped for 223 candidate or tagging SNPs in 30 cell-cycle related genes using the Illumina GoldenGate Assay. The associations between polymorphisms and the risk of colorectal cancer were assessed with multivariate logistic regression. Effect modification by NSAIDs (use &gt;1/month for &gt;1 year) was tested by using a multiplicative interaction term. Haplotype analysis was performed using the haplo.stats R package.

None of the studied SNPs were significantly associated with CRC after multiple test correction. NSAID use lowered the risk of colorectal cancer with an odds ratio (OR) of 0.59 (Confidence interval, CI: 0.51-0.69, p = 9.58*10-11). Several polymorphisms in and near cyclin-dependent kinase 1 (CDK1) and cyclin-dependent kinase 2 (CDK2) showed interaction with NSAID use. However, only one signal remained significant after FDR correction; the homozygous wild genotype (GG) of rs2069408 neutralizes the protective effect of NSAID use (interaction p&lt;0.001, FDR q = 0.018). The effect of NSAID use on CRC risk according the rs2069408 genotypes were the following (OR, 95%CI): 0.82 (0.65-1.02) for GG, 0.51 (0.42-0.61) for GA and 0.31 (0.22-0.45) for AA genotypes. Although non-significant after multiple test correction, interactions with NSAID use was observed at the rs4134950 polymorphism of the E2F3 gene (interaction p = 0.003, FDR q = 0.152) and at rs17187428 (interaction p = 0.004, FDR q = 0.164) and rs773108 (interaction p = 0.005, FDR q = 0.166) in MYC. The haplotype analysis revealed six haplotype blocks in and near the genes E2F3, CDK2, CDK1, CDK6 and MYC that showed significant interaction with NSAID use regarding the risk of colorectal cancer.

A possible mechanism of the interaction between NSAIDs and cell-cycle genes could be mediated via the cell-cycle related effects of MYC, the expression of which is regulated by the Wnt/ß-catenin pathway. This pathway plays a central role in colorectal cancer and was previously found to be inhibited by NSAIDs. The analyses of additional SNPs are ongoing to better understand the mechanism of the interaction between NSAID use and cell-cycle related genes.

Citation Format: Reka Toth, Yesilda Balavarca, Dominique Scherer, Nina Habermann, Katharina Buck, Akke Botma, Elisabeth J. Kap, Axel Benner, Alexis Ulrich, Michael Hoffmeister, Hermann Brenner, Barbara Burwinkel, Jenny Chang-Claude, Cornelia M. Ulrich. Polymorphisms in cell-cycle related genes modify the effect of NSAIDs on the risk of colorectal cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4590. doi:10.1158/1538-7445.AM2015-4590

Abstract 4585: Folate-mediated one-carbon metabolism polymorphisms associated with risk and survival of colorectal cancer

Introduction

Folate-mediated one-carbon metabolism (FOCM) is a key pathway necessary for nucleotide synthesis, DNA methylation, replication and repair. Genetic variants in FOCM genes, especially the MTHFR-C677T polymorphism, have been associated with colorectal neoplasia. Moreover, FOCM is an important target for chemotherapeutic drugs for the treatment of colorectal cancer (CRC), such as 5-fluorouracil (5-FU). We performed a comprehensive assessment of FOCM-related genetic variation in relation to CRC risk and survival in an unfortified population.

Methods

Associations of 457 tagging and candidate SNPs in 47 FOCM-related genes with CRC risk and survival were investigated within a German population-based case-control study (the DACHS- study). Using multivariate adjusted logistic (n = 1754 incident cases and 1781 matched controls) and Cox regression (5 years follow-up of CRC cases only; 585 deceased), we evaluated co-dominant, dominant, and log-additive modes of inheritance. SNPs were genotyped using the Illumina GoldenGate Assay. Correction for multiple testing was performed using false discovery rates (FDR).

Results

Individuals having both variant alleles of a candidate SNP in the ADH1C gene (rs1693482) had a significantly decreased risk of developing CRC (ORhet = 0.94 [95% CI = 0.81-1.10]; ORhzv = 0.74 [95% CI = 0.59-0.92]; p-trend = 0.013). Before correction for multiple testing, 19 nominally significant genetic main effects on CRC risk were observed. None of the studied tagging SNPs was significantly associated with risk after multiple test correction. One polymorphism in the PON1 gene (rs3917538) was significantly associated with overall survival (HRhet = 1.22 [95% CI = 1.03-1.45]; HRhzv = 2.00 [95% CI = 1.48-2.71]; p-trend = 0.01), after correction for multiple testing. Effect modification by 5-FU chemotherapy was observed between two polymorphisms (MTHFR-rs4846047 [Int-pFDR = 0.02] and TK1-rs1811086 [Int-pFDR = 0.02]) for the endpoint overall survival. Cases with variant alleles of these SNPs had a reduced effect of 5-FU on overall survival.

Conclusion

Genetic variation in FOCM appears to be associated with CRC risk and survival. Furthermore, 5-FU might interact with FOCM polymorphisms. Further large investigations are required to replicate our findings.

Citation Format: Akke Botma, Katharina Buck, Yesilda Balavarca, Dominique Scherer, Nina Habermann, Reka Toth, Lina Jansen, Michael Hoffmeister, Hermann Brenner, Elisabeth J. Kap, Petra Seibold, Axel Benner, Alexis Ulrich, Barbara Burwinkel, Jenny Chang-Claude, Cornelia M. Ulrich. Folate-mediated one-carbon metabolism polymorphisms associated with risk and survival of colorectal cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4585. doi:10.1158/1538-7445.AM2015-4585